An implantable cardioverter defibrillator (ICD) delivers high voltage shock pulses to the heart to defibrillate or cardiovert the heart. One or more capacitors in the ICD are charged to a desired voltage to generate the shock pulses. Capacitor charging can cause noise interference that compromises telemetry communication between the ICD and another device, such as an external programmer or home monitor or another implanted device. Telemetry communication may be important during capacitor charging since a clinician may be trying to deliver a command to the ICD to abort the shock pulse delivery. Telemetry communication during capacitor charging also allows a clinician to observe real time data uplinked from the ICD relating to sensed and detected cardiac events. Accordingly, it is important to reduce the noise interference due to capacitor charging during telemetric communications in an ICD.